Abstract: Most of the dam foundation rock mass is granodiorite in the proposed Yalongjiang Mengdigou hydropower station, where intensive development of Hydrothermal alteration rock zone has a single width of 0.5~3m. Deformation test shows that the average deformation modulus of new micro-granodiorite is up to 31.5GPa. The deformation moduli of strong clay alteration rock and weak clay alteration rock are 6.79GPa and 11.10GPa, respectively. Therefore, the existence of intensive altered rock zone can have a significant impact on the deformation characteristics of the dam foundation rock. There are no mature methods to calculate the deformation modulus of the complex combination of rocks with deformation characteristics of significant differences. Therefore, this article is based on the rigid bearing plate deformation test and acoustic test. It uses the nonlinear regression method to analyze the correlation of rock deformation modulus and acoustics. It establishes the rock Vp-E0 correlation formula. Then, it uses the arithmetic average method to calculate the deformation modulus of typical intensive altered rock zone. The result is 18.03GPa and decreases by 42.76%to that of new micro-granodiorite rock. Meanwhile, according to a variety of altered rock band percentage, it uses the weighted average method to calculate deformation modulus of intensive altered rock zone. The result is 19.40GPa and decreases by 38.41%to that of new micro-granodiorite rock. The difference of the two methods is only 7.60%.Comparing with the rigid bearing plate result, the former is more safe and reliable. Thus, the method of nonlinear regression is suggested to calculate the deformation modulus of intensive altered rock zone at Mengdigou hydropower station.